Preliminary evaluation of a self-complementary AAV2/8 vector for hepatic gene transfer of human apoE3 to inhibit atherosclerotic lesion development in apoE-deficient mice.
Hepatic gene transfer of atheroprotective human apoE by recombinant viral vectors can reverse hypercholesterolaemia and inhibit atherogenesis in apoE-deficient (apoE(-/-)) mice. Here, in preliminary studies we assess the effectiveness of a recently developed self-complementary adeno-associated virus (scAAV) serotype 8 vector, driven by a hepatocyte-specific promoter (LP1), for liver-directed gene delivery of human apoE3. Vector viability was validated by transducing cultured HepG2 cells and measuring secretion of apoE3 protein. Male and female apoE(-/-) mice, 6-month old and fed on normal chow, were intravenously injected with 1x10(11) vg (vector genomes) of scAAV2/8.LP1.apoE3; age-matched untreated mice served as controls. In male mice, plasma apoE3 levels were sufficiently high (up to 17 microg/ml) to normalize plasma total cholesterol and ameliorate their proatherogenic lipoprotein profile, by reducing VLDL/LDL and increasing HDL 5-fold. At termination (12 weeks) development of aortic atherosclerosis was significantly retarded by 58% (aortic lesion area 8.2+/-1.4% vs. 19.3+/-2.4% in control males; P<0.001). Qualitatively similar anti-atherogenic effects were noted when female mice were treated, but the benefits were less marked and aortic lesions, for example, were reduced by only 33% (15.7+/-3.7% vs. 23.6+/-6.9%). Although group numbers were small (n=4/5), this gender-specific difference reflected two to three times less apoE3 in plasma of female mice at weeks 3 and 6, implying that gene transfer to female liver using scAAV vectors may require additional optimization, despite their established superior potency to conventional single-stranded (ssAAV) vectors.
Osman
Eyman
E
Department of Medicine, Royal Free & University College Medical School, London, UK.
Evans
Vanessa
V
Graham
Ian R
IR
Athanasopoulos
Takis
T
McIntosh
Jenny
J
Nathwani
Amit C
AC
Simons
J Paul
JP
Dickson
George
G
Owen
James S
JS
D000818:Animals; D001011:Aorta / Q000378:metabolism / Q000473:pathology; D053318:Apolipoprotein E3 / Q000096:biosynthesis* / Q000097:blood / Q000235:genetics; D001057:Apolipoproteins E / Q000172:deficiency* / Q000235:genetics; D050197:Atherosclerosis / Q000235:genetics / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D045744:Cell Line, Tumor; D002784:Cholesterol / Q000097:blood; D000229:Dependovirus / Q000235:genetics*; D004195:Disease Models, Animal; D005260:Female; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D006801:Humans; D008075:Lipoproteins, HDL / Q000097:blood; D008077:Lipoproteins, LDL / Q000097:blood; D008079:Lipoproteins, VLDL / Q000097:blood; D008099:Liver / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D010865:Pilot Projects; D011401:Promoter Regions, Genetic; D012737:Sex Factors; D013997:Time Factors; D014161:Transduction, Genetic
D053318:Apolipoprotein E3; D001057:Apolipoproteins E; D008075:Lipoproteins, HDL; D008077:Lipoproteins, LDL; D008079:Lipoproteins, VLDL; D002784:Cholesterol